Dusk — Erin M. Leaf

Lucy Soren never expected to live through an alien attack. Months later, her nightmares won't let her forget the pain she suffered, or her strange attraction to the man who saved her from certain death.

Sentry Solomon Dusk never wanted to heal a mortal woman, but he can't forget Lucy's bravery or beauty. Even though he vowed to never again fall in love, Lucy attracts him like no other woman ever has before.

When their enemies again slip past the Sentries' defenses, Solomon's only thought is to protect the woman he refuses to love. Lucy's only hope is to run from the danger to her heart. Unfortunately, the fate of the planet rests on their ability to work together. Fear of commitment has no place when love is the only thing that will save them from annihilation.